Method for producing alkali cellulose

Patent metadata

Field	Value
Publication number	US-9416198-B2
Application number	US-201214115252-A
Country	US
Kind code	B2
Filing date	Apr 27, 2012
Priority date	May 2, 2011
Publication date	Aug 16, 2016
Grant date	Aug 16, 2016

Abstract

The present invention relates to a method for producing an alkali cellulose with suppressed decrease in the degree of polymerization as well as with small use amount of a basic compound, and to a method for producing a cellulose ether by using the alkali cellulose thus obtained. Provided by the present invention are: (A) a method for producing an alkali cellulose, comprising Step 1 wherein a cellulose-containing raw material (I) is treated by a pulverizing machine thereby obtaining a cellulose-containing raw material (II) which contains a cellulose having crystallinity in the range of 10 to 55% and Step 2 wherein the cellulose-containing raw material (II) obtained in Step 1 is added by a basic compound with the amount thereof being in the range of 0.6 to 1.5 mol relative to 1 mol of an anhydroglucose unit that constitutes the said cellulose as well as by water with the amount thereof being in the range of 20 to 100% by mass relative to the said cellulose thereby obtaining the alkali cellulose; and (B) a method for producing a cellulose ether by reacting the alkali cellulose produced by the foregoing production method with an etherification agent.

First claim

The invention claimed is:

1. A method for producing an alkali cellulose comprising:
Step 1 wherein a cellulose-containing raw material (I), having water content in the range of 0.01% to 10% by mass relative to the cellulose and being pulp, paper plant stem, or plant shells, is treated by a pulverizing machine thereby obtaining a cellulose-containing raw material (II) which contains a cellulose having crystallinity in the range of 10 to 55%,
Step 2 wherein the cellulose-containing raw material (II) obtained in Step 1 is combined with:
i) a basic compound with the amount thereof being in the range of 0.6 to 1.5 mol relative to 1 mol of an anhydroglucose unit that constitutes the said cellulose in the cellulose containing raw material (II) and
ii) water in the range of 20 to 100% by mass relative to the said cellulose in the cellulose containing raw material (II), and
Step 3 wherein aging is carried out by increasing the temperature range to 35 to 90° C. for the time period of 0.1 to 24 hours thereby obtaining an alkali cellulose.

2. The method for producing the alkali cellulose according to claim 1 , wherein the water content in the cellulose-containing raw material (I) in Step 1 is in the range of 0.01% to 7% by mass relative to the cellulose.

3. The method for producing the alkali cellulose according to claim 1 , wherein the basic compound is an alkaline metal hydroxide.

4. A method for producing a cellulose ether, further comprising the step wherein the alkali cellulose produced by the production method according to claim 1 is reacted with an etherification agent.

5. The method for producing the cellulose ether according to claim 4 , wherein the alkali cellulose and the etherification agent are reacted in the presence of a non-aqueous solvent with the amount thereof being in the range of 1 to 100% by mass relative to the cellulose in the cellulose-containing raw material (I).

6. The method for producing the cellulose ether according to claim 4 , wherein the etherification agent is one or more kinds selected from the group consisting of ethylene oxide, propylene oxide, glycidol, chloroacetic acid, sodium chloroacetate salt, glycidyl trimethyl ammonium chloride salt, and 1-chloro-2-hydroxypropane-3-trimethyl ammonium chloride salt.

7. A method for producing a cellulose ether, comprising:
reacting the alkali cellulose produced by the production method according to claim 1 with an etherification agent,
wherein use amount of the etherification agent is in the range of 0.001 to 50 mol relative to total 1 mol of the anhydroglucose unit of the cellulose and of the anhydroglucose unit of the alkali cellulose in the alkali cellulose-containing mixture produced by the production method according to claim 1 .

8. The method for producing the cellulose ether according to claim 5 , wherein the non-aqueous solvent is selected from the group consisting of a secondary or a tertiary lower alcohol having 3 to 4 carbon atoms, a ketone having 3 to 6 carbon atoms, an ether, a non-protonic polar solvent, and mixtures thereof.

9. The method for producing the alkali cellulose according to claim 1 , wherein crystallinity of the cellulose in the cellulose-containing raw material (II) after the treatment by a pulverizing machine in Step 1 is 10-40%.

10. The method for producing the alkali cellulose according to claim 1 , wherein the treatment by a pulverizing machine in Step 1 is carried out by using a pulverizing machine selected from the group consisting of a roll mill, a vertical roller mill, a vessel-driven medium mill, a medium-stirring mill, and a compressing shear mill.

11. The method for producing the alkali cellulose according to claim 1 , wherein crystallinity of the cellulose in the cellulose-containing raw material (I) in Step 1 is 60% to 95%.

12. The method for producing the alkali cellulose according to claim 1 , wherein amount of the basic compound to be added in Step 2 is 0.7-1.5 mol by mol, relative to 1 mol of the anhydroglucose unit that constitutes the cellulose in the cellulose-containing raw material (II).

13. The method for producing the alkali cellulose according to a claim 1 , wherein the aging is carried out at 40-90° C.

14. The method for producing the alkali cellulose according to claim 1 , wherein the aging is carried out at 35-75° C.

15. The method for producing the alkali cellulose according to claim 1 , wherein the average degree of polymerization of the cellulose in the cellulose-containing raw material (I) in Step 1 is 100 to 10000.

Assignees

• Miyoshi Eisuke
• Yoshida Yutaka
• Miyasato Ryo
• Imori Yoichiro
• Nishioka Toru
• Kao Corp

Inventors

• Miyoshi Eisuke
• Yoshida Yutaka
• Miyasato Ryo
• Imori Yoichiro
• Nishioka Toru

Classifications

• C08H8/00

  Macromolecular compounds derived from lignocellulosic materials {(pretreatment thereof B27N)} · CPC title

• C08B11/08

  with hydroxylated hydrocarbon radicals; Esters, ethers, or acetals thereof · CPC title

• C08B11/02

  Alkyl or cycloalkyl ethers · CPC title

• C08B1/06

  Rendering cellulose suitable for etherification {(etherification per se C08B11/00)} · CPC title

• C08B11/14

  with nitrogen-containing groups · CPC title